Alpha (silylmethyl) sulfides and the corresponding siloxanes

ABSTRACT

BIS AND TRIS-ALPHA-SILYL SULFIDES OF THE FORMULA   R&#39;&#39;-S-C(-R&#34;)Y(-SI(-R)3)X   WHERE X IS 2 OR 3 AND Y IS 0 OR 1, ARE PREPARED BY THE REACTION   R&#39;&#39;-S-C(-R&#34;)Y(-SI(-R)3)X-LI   PLUS R3SICL. WHEN AT LEAST ONE R IS A SILANOL GROUP OR A HYDROLYZABLE GROUP THE CORRESPONDING SILANOL GROUP OR A HYDROLYZABLE GROUP THE CORRESPONDING SIOLOXANES ARE PREPARED BY HYDROLYZING AND/OR CONDENSING SUCH COMPOUNDS. THE COMPOSITIONS ARE USEFUL AS ANTI-OXIDANTS AND AS LUBRICATION ADDITIVES.

United States Patent ()flice Patented Jan. 12, 1971 3,555,067 ALPHA (SILYLMETHYL) SULFIDES AND THE CORRESPONDING SILOXANES Gary E. Le Grow, Midland, Mich., assignor to Dow Corning Corporation, Midland, Mich., a corporation of Michigan No Drawing. Filed Dec. 13, 1968, Ser. No. 783,749

Int. Cl. C07f 7/08, 7/10 US. Cl. 260-4482 2 Claims The compositions are useful as anti-oxidants and as lubrication additives. 1

This invention relates to compounds of the formula RI/y (R Si)X( )SR' in which at is an integer from 2 to 3 inclusive, y is an integer from to 1 inclusive, R is a hydrocarbon radical free of aliphatic unsaturation, hydrogen, OH or NX in which X is an alkyl radical, R" is hydrogen or a hydrocarbon radical free of aliphatic unsaturation and R is an alkyl or a phenyl radical.

The silanes of this invention are prepared by reacting compounds of the formula R SiCl with organolithium compounds of the formula n which in turn are prepared by the method disclosed in applicants copending application Ser. No. 783,748 entitled Organolithium Derivatives of Alpha-Silylmethyl Sulfides filed concurrently herewith, the entire disclosure of which is hereby incorporated by reference.

The reaction of the chlorosilanes with the lithium derivatives is carried out in the normal manner for reacting chlorosilanes with organometallic compounds. These methods are well known in the art.

As stated above R can be a hydroxyl group. These silanols are prepared by careful hydrolysis of those silanes in which R is a X N group using an acid such as acetic acid as a catalyst. Silanols can also be prepared by reacting those silanes in which at least one R is hydrogen with water. The latter is best done in the presence of a palladium catalyst under neutral conditions as shown in U.S. Pat. 3,328,448.

This invention also relates to siloxanes having at least one unit of the formula Rn ny in which x is an integer from 1 to 3 inclusive, z is an integer from 0 to 2 inclusive, y is an integer from 0 to 1 inclusive, the sum of x+z being at least 2 and the sum of x+y+z being no greater than 3, n is an integer from 0 to 2, R is a hydrocarbon radical free of aliphatic unsaturation,a hydrogen atom, a hydroxyl group or a radical of the formula NX in which X is an alkyl radical, R" is a hydrocarbon radical free of aliphatic unsaturation or a. hydrogen atom, and R is an alkyl radical or a phenyl radical, any remaining siloxane units being of the formula Ammo,

in which A is a hydrolyzable group, a hydrogen atom, a hydroxyl group, a hydrocarbon radical, or a halohydrocarbon radical and in has an average value from 0 to 3 inclusive.

The siloxanes of this invention are prepared by conventional methods for preparing siloxanes. In other words, they are prepared by the hydrolysis and/or condensation of the above defined silanes in which R is a hydrolyzable or a condensable group. As is well known in the siloxane art for one to have uncondensed hydroxyl groups remaining in a siloxane, the condensation must be carried to a point short of complete condensation. In order to have hydrolyzable groups remaining in the siloxane, the hydrolysis must be carried outwith insuflicient water to react with all of the hydrolyzable groups. By selecting the proper ratio of R groups to silicon, siloxanes can be prepared in the form of fluids, resins or rubbers. Furthermore, they can be either homopolymers or copolymers of the various sulfur containing groups, or they can be ccpolymers of the siloxane units of this invention and conventional siloxane units of the type AmSi0 tions fo this invention is the group i ESKIJSiE and Of course, it is not necessary that each silicon have an oxygen atom attached thereto. In those cases the following configurations are obtainable:

As has been mentioned the siloxanes containing the above sulfur groups can be copolymerized with siloxane units of the formula A SiO such as A SiO A SiO, ASiO and Slog.

For the purpose of this invention R can be any hydrocarbon radical free of aliphatic unsaturation such as alkyl radicals, such as methyl, ethyl, butyl, isobutyl, hexyl, octadecyl or myricyl; any aryl radical such as phenyl, xenyl, naphthyl or anthracyl; any alkaryl radical such as tolyl, xylyl, ethyl henyl, or isopropylphenyl and any aralkyl radical such as benzyl, beta-phenylethyl or beta-phenylpropyl.

R" can be any hydrocarbon radical free of aliphatic unsaturation such as alkyl radicals such as methyl, ethyl, isobutyl, hexyl, myricyl; any aryl radical such as phenyl, xenyl, naphthyl or anthracyl; any alkaryl radical such as tolyl, Xylyl or ethylphenyl or any aralkyl radical such as benzyl, beta-phenylethyl or beta-phenylpropyl.

X is any alkyl radical such as methyl, ethyl, isopropyl or octadecyl and R can be any alkyl radical such as those shown for X or the phenyl radical.

For the purpose of this invention A can be any hydrocarbon radical such as any alkyl radical such as methyl, ethyl, octadecyl, isopropyl or myricyl; any alkenyl radical such as vinyl, allyl, hexenyl or butadienyl; any cycloaliphatic hydrocarbon radicals such as cyclopentyl, cyclohexyl or cyclohexenyl; any aromatic hydrocarbon radical such as phenyl, xenyl, naphthyl, anthracyl, tolyl, xylyl or ethylphenyl; and any aralkyl radical such as benzyl, betaphenylethyl or beta-phenylpropyl.

A can also be any halogenated hydrocarbon radical such as chloromethyl, chloroethyl, gamma-chloropropyl, bromo-propyl, 3,3,3-trifiuoropropyL- perfluorovinyl, ch

rocyclohexyl, bromocyclohexenyl, chlorophenyl, QQOQOL-lfi fluorotolyl and B-chlorophenylpropyl. p

A can also be any hydrolyzable group* such as halogen such as Cl, Br or F; hydrocarbonoxy such asmethoxy, ethoxy, isopropoxy, octadecyloxy, fl-methoxyethoxy, allyloxy, -O(CH CH O) C H or phenoxy; halogenated hydrocarbonoxy such as chloroethoxy, bromophenoxy, chlorocyclohexyloxy or chlorobenzyloxy; acyloxy radicals The term hydrnlyznhle means that the group is removed from the Si by Water at room temperature.

. t el as as tqxytbaz x e x a ylyl y q y t etoxy;

R'C NO radicals such as (CH C=NO,

aminoxy radicals such as (CH ;NQ or H ,oinmo' amino radicals such. as (CH N- or (C H N'-; -CEN, N=C=O, NH sulfate. radicals of the formula --OSO OR where R is H, methyl, ethyl orphenyl and sulfonate radicals such as I 0sR where R is phenyl or alkyl.

The compositions of this invention are useful as antioxidants for siloxane fluids and as additives for hydrocarbon oils to increase the lubricity under high pressure. The compounds of this invention offer a Wide variety of selectivity in that one can adjust the solubility of the sulfide to fit the base materials by selecting the proper substituent R group on the silicon atom and for the substituent R group on the carbon atom.

The following examples are illustrative only and should not be construed as limiting the invention which is properly delineated in the appended claims.

EXAMPLE 1 0.125 m. of (CH SiCH SCH was dissolved in 200 ml. of dry tetrahydrofuran and cooled to 25 C., 0.125 m. of n-butyllithium in ml. of hexane was added slowly with stirring. The solution was warmed to room-temperature and 0.15 m. of trimethylchlorosilane was added. The crude reaction product was extracted with diethylether and then washed with water until neutral and dried. The product was separated by gas liquid chromotagraphy and the compounds {(CH Si} CHSCH and {(CH Si} CSCH were both obtained. The product were identified by nuclear magnetic resonance spectra, elemental analysis and mass spectrographicanalysis. The properties for {(CH Si} CI-I SCH were boiling point 41.5 C. at .5 mm., 11 1.4680, D 0.864 and 'R observed 0.3217 and calculated 0.3208. The compound I had a melting point of to C.

The compound having 3 silyl groups was formed by, the in situ trans metallation of the {(CH Si} CHSC H o s CH5 was prepared as shown in applicants aforesaid copending application. .Whenthis compound is reacted with a in accordance with the procedure of Example 1 the compound is obtained.

When this compound is hydrolyzed in the presence of CH3 {H(CHa)2Si]2( S CH3 is obtained.

When the latter compound is reacted with water at 25 5 to 30 C. in the presence of palladium on charcoal at a pH of from 7.6 to 6.8, the diol .1% acetic acidsolution in water and thereafter allowed 10 is obtained to condense the disiloxane is reacted with H( CH SiCl in accordance with the proce- 2 dures of Example 1,

When this diol is condensed by heating to 100 C. in the presence of sodium phenoxide as a catalyst a fluid siloxane of the unit formula a)2 S 3): 0 Sl--C-Si is obtained.

EXAMPLE 4 When the following Li compounds are reacted with the following chlorocompounds in accordance with the procedure of Example 1, the following compounds are obtained:

7 M H EXAMPLE 5 I EXAMPLE When the following silanes are hydrolyzed and/or when 1 mole of cohydrolyzed and condensed the following siloxanes are I obtained: (CHa)zSi 20113011,

Silane 1 Silane 2 Siloxane (01192 92 C1sHa7SiCHSC1aH37 OlsHaySifilHSiOz g H w aMa SC1s a7 I s V,

{ 1 a (CH3)2} 3):} CQH5CHCHZA1- z-CSC;H CsH5CHCH2Si- 2(|]Si0 a)al2 3 9 is reacted with 2 mols of (CH Si(OOCCH at 50 C. a compound of the average formula 2. A siloxane having at least one unit of the formula (R Si).(Oa nSi CSR 2 x in which x is an integer from 1 to 3 inclusive, z is an integer from 1 to 2 inclusive,

y is an integer from 0 to 1 inclusive,

n is an integer from 0 to 2 inclusive, the sum of x+z being at least 2 and the sum of x+y+z being no greater than 3,

R is a hydrocarbon radical free of aliphatic unsaturation, the hydrogen atom, the hydroxyl group or NX in which X is an alkyl radical,

R" is a hydrocarbon radical free of aliphatic unsaturation or a hydrogen atom,

R is an alkyl radical or a phenyl radical, any remaining siloxane units being of the formula A sio 2 in which A is a hydrolyzable group, a hydrogen atom,

a hydroxyl group, a hydrocarbon radical or a halohydrocarbon radical, and in has an average value from 0 to 3 inclusive.

References Cited UNITED STATES PATENTS 2,960,492 11/1960 Morton et a1. 260448.2XR 3,078,292 2/1963 Prober 260448.2(N)

TOBIAS E. LEVOW, Primary Examiner P. F. SHAVER, Assistant Examiner US. Cl. X.R. 

